Method and means for manipulation of sound records



Oct; 5, 1937. 5 REGAN ET'AL I 2,094,847

' METHOD AND MEANS FOR MANIPUIJATION OF SOUND RECORDS Filed April 10,1936 4 Sheets-Sheet 1 INVENTORS Q gym ATTORNEYS a. P. REGAN ET AL Oct.5, 1937.

METHOD AND MEANS FOR MANIPULATION OF SOUND RECORDS 4 Sheets-Shed 2 FiledApril 10, 1956 INVENTORS I MC /a/nwn/ BY ATTORNEYS- Oct 5, 1937. G. P.RE AL 2,094,847

METHOD AND'MEANS FOR MAN IPULATION OF SOUND RECORDS Filed April 10, 19364 Sheets-Sheet 3 INVENTORS ATTORNEYS Oct. 5, 1937. a. P. REGAN ET ALMETHOD AND MEANS FOR MANIPULATION OF SOUND RECORDS 4 Sheets-Sheet 4Filed April 10, 1936 uuxmwt INVENTORS Patented Oct. 5, 1937 UNITED STATMETHOD AND MEANS FOR MANIPULATION OF SOUND RECORDS Application April 10,1936, Serial No. 73,670

21 Claims.

This invention relates to means and methods whereby sound films or othercontinuous strips or members bearing reproducible sound recordings maybe manipulated for various purposes. For example, during editing ofsound recordings for use in the reproduction of motion pictures withaccompanying sound, it is necessary at times .to locate and carefullyidentify a specific phrase in a long continuous record so that thisphrase may be deleted or modified in the final print. No methods areavailable at present whereby this can be accomplished readily andaccurately. Numerous other instances occur where it is highly desirableto control the reproduction of a continuous sound recording and some ofthese instances will be described in detail hereinafter.

Generally stated, the present invention relates to a method whereby acontinuous film carrying a plurality of sound modulation groups inspaced sequential alignment thereon may be automatically manipulated insuch manner that each one of the sound modulation groups may bereproduced in its entirety and the progress of the film automaticallystopped immediately in advance of the reproducing unit. In this mannerthe continuous film may be caused to be reproduced in a step-by-stepprogression, each step representing a complete sound modulation group,such as a phrase, word or sound eifect. Careful analysis of each phrase,sentence or continuous sound may thus be attained.

The invention also relates to means whereby the method may be carriedout in a facile and accurate manner. The device of this inventionincludes a double pick-up, one of said pick-ups being employed inactually reproducing the sound so that it may be heard and studied,whereas the other pick-up acts as a control and automatically stops thefilm immediately before a succeeding sound reaches the reproducing unit.This latter or controlling pick-up operates relays which automaticallydeenergize the means employed in movingthe film past the reproducingpick-up.

For purposes of simplification, reference will hereinafter be made'tostrip film and photographic sound records carried thereby, it beingunderstood that the invention is not limited to its use on continuousstrip film nor to any particular type of sound recording. Anyreproducible sound record may be manipulated in accordance with thisinvention.

An object of this invention, therefore, is to disclose and provide meansfor manipulating strip film carrying a plurality of sound records inspaced succession whereby desired portions may be reproducedautomatically.

Another object of the invention is to disclose and provide a methodwhereby the study, analysis, editing, dubbing and modification ofcontinuous sound recordings may be performed rapidly and accurately.

A further object of the invention is to disclose and provide a noveloptical system whereby each and every sound modulation group carried bya continuous film may be reproduced in its entirety Without thenecessity of reproducing a complete succession of such groups.

Another object is to disclose and provide an electrical relay systemwhereby the continuous progress of a film bearing a plurality of soundrecords in spaced succession may be terminated immediately in advance ofa succeeding sound record.

These and other objects, modifications, adaptations and various uses ofthe methods and means of this invention will become apparent to thoseskilled in the art from the following detailed description of one formof the invention and several modes of operation which can be employed.It is to be understood that the following description is simplyillustrative of one embodiment of the invention.

In describing the methods and devices, reference will be made to theappended drawings, in which:

Fig. 1 is a front elevation of a double optical system which may beemployed.

Fig. 2 is an enlarged view, partly in section, of the pick-up andmarking devices embodied in the apparatus shown in Fig. 1.

Fig. 3 is a vertical transverse section taken along the plane IIIIII ofFig. 1.

Fig. 4 is a simplified wiring diagram diagram- 7 matically illustratingcertain of the elements employed in carrying out the method of theinvention.

Fig. 5 is an enlarged view of a modified form of control device whichmay be embodied in the apparatus shown in Figs. 1, 2, and 3.

Fig. 6 diagrammatically represents a portion of motion picture filmadapted for use with the modification of Fig. 5.

In the description given hereinafter, reference will be made to soundrecords or sound recordings. As stated hereinbefore, the invention doesnot relate to any particular method of record ing or reproducing-soundbut embraces all known methods of recording and reproduction. More- W6in the description given hereinafter, reference will be made to groupsof modulations. By this term reference will be made to a sequence ofmodulations impressed upon or photographically or otherwise recordedupon strip film metal, wire, or the like. The term modulation group.refers to a sequence of modulations representing sound and may includebut a single note or a phrase, sentence, or other substantiallycontinuous sequence of sounds. Each modulation group, irrespective ofits length or brevity, is spaced from an adjoining group by a nullperiod or space period during which nosound or modulation em'sts. Suchnull period or space period may consist of a period of time ranging fromone-twentieth of a second to many minutes. In a single modulation groupthere may be shorter fractional instants during which no actualmodulation exists on the record but because of the shortness of suchperiod the modulation group is not disrupted and to all intentsandpurposes constitutes a continuous sound.

The method of the invention comprises intermittently moving a stripcarrying sound modulation groups in spaced succession past a reproducingunit and stopping the film or strip at points immediately in advance ofa succeeding sound modulation group. This is accomplished automaticallyby the apparatus of this invention and although the device described indetail hereinafter will not recognize null periods or space periodsshorter in length than. about one-fifth of a second, it is readilyapparent that by changing the electrical characteristics of the relaysyse tems embodied in the device that even shorter null periods may berecognized by the device and cause the intermittent movement of the filmstrip to be terminated whenever'such shorter null period appeared. Lessselective devices may not recognize null periods which are shorter thanone-half or even one second.

In the device shown in the drawings, a continuous film carryingmodulation groups in success'ion on a sound track is fed from a reel lin the magazine 2 through the device and rewound upon the reel 3. Thefilm 4 may pass over an idler roller 5 and then into contact with adriven sprocket B. The film ismaintained in contact with such drivensprocket by means of rollers l.

Thereafter the film passes over rollers 8, '9, and Ill and through agroup of rollers indicated at i I by which it isfed over a drum E2, thedrum being also driven. The film then passes over another group ofrollers indicated at it and over the rollers I4, l5, and It. It againcontacts with the sprocket 6, passes over another spring-tensioned idlerroller ll and is returned to the take-up reel 3 of the magazine 2.

The sprocket roller 6 and the drum l2 are also indicated in the Wiringdiagram, Fig. 4. The drum 12 is shown in greater detail in Figs. 2 and3. As there shown, the drum is mounted upon a shaft it which is coupledto the shaft '59 of a synchronous motor 2o through an electromagnetic,clutch and brake, generally indicated at 2 l. The interior of the druml 2 is maintained under vacuum, such vacuum being supplied to theinterior of the drum through a stationary fitting 22 provided with arotatable member 23 which forms a tight running fit with the interiorsurfaces of the drum it. The conduits 24 and 25 connect the interior ofthe drum III? with a source of vacuum suchas a vacuum pumpuoperated bythe motor 25 (see Fig. 4). The film 4 passes overthe surface of therotatabledrum l2 and extends, over the forward edge of the drum tooccupy the position 4' (Fig. 3).

His tobe understood that the surface of the drum i2 is perforated sothat the suction or indicated in dotted lines at vacuum existing withinthe drum I2 causes the' reproducing pick-up is indicated at 28 and arelay or controlling pick-up is indicated at 29. These pick-up devicesmay be in the form of suitable photoelectric cells capable of receivinglight modulated by the record borne by the film i. For example, thecontrolling pick-up 29 may receive light from a source 38, the lightbeing directed by means or" a telescope or objective lens system3ithroughthe sound track area of the film while it is occupying theposition shown'at 4 on the drum I2, the modulated light being thenreflected by means of a prism or similar reflective element 32 upon thecontrolling pick-up or photoelectric cell 29. The reflective element 32may be mounted upon a ring or, sleeve 34 adjustably positionable aboutthe stationary fitting 22, as by means of the set screws 35. Thephotoelectric cell 29, light source 33 and lens system 3| may be mountedupon a bracket 36 which is also adjustably positionable as by means ofthe lock screw '31 operating in the slot 38. The linear spacing alongthe periphery of the drum l2 of the axes of the optical systems 3|, and3! may thus be varied.

It will be evident that when film is passing through the device in thedirection of the arrows,

. the sound modulation groups carried'by the sound track of said filmwill first pass in operative relation to the control pick-up 29 and thenpass over the reproduction pick-up 28.

By referring to' Fig. 4, the electrical relationships of the variousunits will become apparent. The'sprocket G'is driven by means of avariable speed motor indicated at V. S. IVL, said motor being providedwith a resistance in series which may be'varied so as to insure arotational speed substantially equivalent to the rotational speed of thesynchronous motor 26 which drives the drum l2. Clutch and brake coils,generally indicated at '40, control the operation of the sprocket 6 andare embodied'in an electromagnetic clutch and brake unit interposedbetween the motor and the sprocket 6. Similar clutch and brake coils 4|are interposed between the motor 26 and the drum l2. A three phase,220volt source of current is indicated at 42. The reversing switch S-|controls the operation of the motor 2d. The switch S2 controls the motor26 which runs the vacuum pump supplying vacuum to the conduits 24 and 25and the interior of the drum l2.

,The reproducing'pickmp 28. converts the light modulated by the soundmodulations borne by the film 4 into an oscillatory current which isthen sent through a preamplifier i3 and a main amplifier 44 from whichthe audio currents are sent to a reproducing unit 35, from which theymay be heard. The control pick-up 29 converts light modulated by thesound modulations of the film 4 into an oscillatory current which maybesent through a preamplifier 46 and another amplifier G'i, which thensupplies currentto a transformer feeding the grid of a thermionic valveVl. The variable speed motor V-S -M maybe supplied with current such asnormal. 110 volt D. C. from terminals indicated at 48.

Any, suitable arrangement of relays capable of attaining the desiredresults may be employed but for purposes of illustration the wiringdiagram shows a relay system which embodies the relays E, F, G, and M.In starting operations, the variable speed motor is started by closingswitch S-3 and the synchronous motor 20 is started by closing the switchSI. The switch S2 is also closed so as to operate the vacuum pump. Thesprocket 6 and the drum I2 are not rotated, however, since the brakecoils are energized due to a locking circuit which is closed by thedeenergized relay M.

In order that the film, bearing a plurality of sound modulation groupsin spaced succession, be automatically intermittently moved past thereproducing unit 28 and automatically stopped at a point immediately inadvance of a succeeding modulation group carried by such film, the relaykey is depressed, closing a circuit between the grid of the valve V2 andthe ground, thus removing the C bias and causing an increase in platecurrent of said tube V-2. This increase is sufiicient to energize therelay E. When relay E is energized, the upper or make contacts of therelay close a circuit through the winding of relay M, thus energizingit. The relay M closes a circuit to'the clutch solenoids, causing thedrum l2 and the sprocket 6 to rotate, moving the film past the controlpick-up 29 and the reproducing pickup 28.

At the time the relay E is energized, the lower make contacts close alocking circuit consisting of the plate of the tube V-2 through therelay E, break contacts of relay F and the filament return circuit.Attention is called to the fact that the relay E is in parallel with theplate supply of the tube V--2 only when relay E contacts are closed andwhen the locking circuit can be completed through relay F or G.

The general sequence of operations, therefore, which takes place whenthe relay key is depressed and the circuit closed, consists of thefollowing: relay E is energized, relay M is energized, the brake coilsare deenergized and the clutch coils are engaged, relay F is energizedand relay G is energized. All these operations consume but a very shortperiod of time. When the relay G is energized, the holding or lookingcircuit is closed, which keeps relay M and the clutch energizedregardless of the variations in energy supply to relays E or F.

As soon as the film starts moving past the pick-ups 29 and 28, a soundmodulation group carried by such film will obviously cause oscillatorycurrent or electrical energy to be supplied from the amplifier 41 to thetransformer feeding the grid of tube V-l, causing an increase of platecurrent through the winding of relay F. When F is energized, it tends toopen a locking or holding circuit of relay E but this does not occurbecause normally the relay key is depressed for a longer interval. oftime than that required for the sequence of operations and while suchkey is depressed, E continues to be energized. When F is energized dueto flow of energy from the amplifier 41 of the control pick-up 29, acircuit through G is closed, causing G to become energized.

The circuit which energizes G includes the lower make contacts of therelay F, the winding of relay F to one pole of the 110 volt line andfrom the other pole of the 110 volt line through the 14,000 ohm resistorto the contacts of F. When the circuit is closed and G is energized, theholding circuit and relays E, M and the clutch solenoids will remainenergized regardless of whether or not the relay key is depressed. As aresult, relays E, M, F, and G remain energized as long as any modulationgroup is passing the control pick-up 29.

As soon as no modulation group is passing the control pick-up 29 (thatis, whenever a null space or period appears on the sound track), relay Fis deenergized. When F is deenergized, the looking circuit to relay E isclosed through the break contacts. Relay G also deenergizes. As long asa null period is passing the control pick-up 29, the holding circuit ismaintained through the break contacts of relay F. In this manner thefilm is driven past the pick-ups 28 and 29 as long as no modulationgroup is carried by the film past the control pick-up 25.

As soon as a succeeding modulation group appears on the film inoperative relation to the control pick-up 29, relay F is againenergized. This immediately breaks the holding circuit to relay E, whichin turn opens the circuit to relay M. Relay M opens the clutch circuit,disconnecting the motors from the sprocket 6 and drum i2 and appliesenergy to the brake coils, bringing sprocket and drum to a quick stop;During this part of the operation, relay G does not close the lockingcircuit because relay E is deenergized before relay G has had time tooperate.

When the drum comes to a stop, reproduction of sound from the trackceases. Relay F is deenergized and the entire system is restored to itsinitial condition, the various contacts being in the positions indicatedin Fig. 4.

It will be evident that in the operation described, a group ofmodulations has been reproduced and the film moved throughout a completegroup of modulations and for a length equivalent to the length of anynull or blank period following such group of modulations, the film beingstopped with the reproducing pick-up 28 immediately in advance of thebeginning of the succeeding group of modulations.

If it is desired to move the film independently without causing themechanism to automatically stop the film at the beginning of asucceeding modulation group, then the clutch key can be depressed, saidclutch key actuating relay M to energize the magnetic clutches and openthe circuits and brake coils.

When, during analysis of a film by means of the device describedhereinabove, it is desired to mark or identify a particular point on thefilm or a particular modulation group which is being reproduced, themarker key may be depressed, such marker key energizing a solenoid 50which causes the marker point 5i to bear against the film carried on thedrum l2. Visual means of identifying a particular section is thusprovided.

As pointed out hereinbeiore, the film is brought up to the desiredlinear speed almost instantaneously immediately upon engagement of thesprocket 6 and drum 2 with their respective motor drives through themagnetic clutches. The drum i2 is not provided with sprocket teeth whichmay tear the film but instead holds the film in close contact therewithby reason of the applied vacuum.

As shown in Fig. 1, an appreciable loop of film exists between thesprocket t and the drum I2. In "the event the sprocket s is moved at aslightly lower speed,than the drum l2, the loop passing over the rollers8, 9, it, etc., will become shortened. Such shortening of the loop willcause the arms 52 and 53 to pivot about the point 54, it beingunderstood that the arms 52 and 53 are rigidly connected around thepivot point and carry the rollers 8, 9, ill, and l4, l5, l6,respectively. Apivotal motion of the arms 52 and 53 as described causesthe contact finger 56 to move over a plurality of contact points whichvary the resistance,

interposed in the shunt circuit of the motor, speeding up the variablespeed motor. Very gentle film tension on either side of the balance armswill thus cause the contact point 56 to hunt back and forth across anormal point at which the linear speeds of the sprocket 6 and the druml2 are equal. A balanced condition is eventually reached Without anyslippage, tearing of the film, or other difficulties.

The method and apparatus of this invention are particularly adapted forthe analysis of sounds recorded photographically on film. The doublephotoelectric cell system in which one cell acts as a controllingelement whereas the other reproduces the sound, is a distinctivefeature. The provision of means whereby the film may be rapidly (almostinstantaneously) brought up to full linear speed and as readily stopped,as by means of the magnetic clutches and brake coils, permits carefuland accurate analysis of each phrase, word, sound or other modulationgroup. Attention is called to the fact that all modulation groups arecompletely reproduced, that is, no portion of the group is lost duringstarting or stopping. When it is desired to prepare a cue film for theinstruction of foreign artists (as in the preparation of foreignversions), the original or American version may be analyzed inaccordance with this method and suitable cue marks appliedthereto bymeans of the marker, switch, solenoid and pencil. Precise instants ofinitiation and cessation of sound can thus be identified and greatlyfacilitate subsequent dubbing or translation processes. Moreover, themethod and apparatus may be used in selecting a desired portion of alengthy record whenever such portion has either particularly good or badcharacteristics.

The apparatus may also be used for rerecording purposes as where severalsound efiects are to be rerecorded or combined. It may also be usedin'cutting, editing and like work and may be combined with a viewingmachine or projector so that the action as well as the sound may beanalyzed.

The method and apparatus may also, be used' to great advantage inteaching musi The basis of all musical education is repetition, studyand familiarity with themes, constructions, passages, etc. Because ofits ready manipulation, reversibility, etc., recordings of famouscompositions by outstanding artists and/or composers can be reproduced,reversed, repeated, analyzed and studied at leisure. The apparatus maybe quickly stopped and reversed by introducing electromagnetic brakes onthe motor shafts (separate from the brake coils acting directly on thesprocket and drum shafts) and by providing suitable reversing switchesso that reversal to standard linear speed can be attained in a veryshort interval.

In many dramatic plays and during radio' broadcasting programs, it isdesirable that vari ous sound effects, incidental music, etc, be supplied at stated intervals. Said sound effects may be carried by arelatively short length of film, the null or blank spaces between soundmodulation groups being as short as 1 inch, whereupon, by the operationof this invention, the desired sound effects may be instantaneouslyreproduced immediately upon closure of the relay key.

It is to be noted that even though a second sound eifect is not to occurfor a full minute after the completion of the first, it is not necessarythat ninety feet of blank film exist between the two soundeifects sincethe device will automatically stop' the film with the reproducingpick-up 28 immediately in advance of the secondary group of modulations.When the proper cue is given on the set or stage, the relay key isdepressed and the reproduction of the secondary modulation group isinstantaneously initiated.

Instead of employing a control pick-up such as the control pick-up 25,the various sound effects may be carried by a film provided withperforations such'as the perforations 69 and. BI shown in thefilm 59(Fig. 6) the space between perforations constituting a completemodulation group. Instead of the photoelectric control pick-up 29, aspring contact finger 62 is employed, said contact finger being pivotedas at 63, the end of the spring finger being capable of contacting thedrum l2 through a perforation such as the perforation 5%. Contact of thefinger with the drum closes a control circuit, terminating furtherprogress of the film by reason of a deenergization of the clutch and asimultaneous energization of the brake coils.

When the relay key is operated, however, the film motion is initiatedand as long as the finger 62 rides upon the film, it is insulated fromthe drum. The spring contact finger 62, therefore, acts in a manner verysimilar to that of the control pick-up in that the machine will stop atdefinite predetermined places on the film sound record.

Those skilled in the art will appreciate that numerous changes andmodifications can be made in the general arrangement and construction ofthe devices operating in accordance with this invention and that themethod of the invention is applicable to numerous uses. All changes,modifications and adaptations coming within the scope of the appendedclaims are embraced thereby.

We claim:

1. In a machine for manipulation of strip film carrying a plurality ofsound modulation groups in succeeding spaced relation, the combinationof a reproducing pick-up in operative relation to said film; a relaypick-up in advance of said reproducing pick-up, said relay pick-up beingadapted to convert sound modulation carried by the strip film intoelectrical energy; means for driving said strip film past said relaypick-up and recording pick-up in succession; means for energizing saiddriving means; and a relay system adapted to maintain said driving meansoperative while a sound modulation group carried by said film is movingpast said relay pick-up and during any null period between saidmodulation group and a succeeding sound modulation group, said relaysystem being adapted to stop said driving means when a succeeding soundmodulation is moved past said relay pick-up.

2. In a machine for manipulation of strip film carrying a plurality ofsound modulation groups in succeeding spaced relation, the combinationof a reproducing pick-up in operative relation to said film; a relaypick-up in advance of said reproducing pick-upj means for driving saidstrip film past said relay pick-up and reproducing pickup in succession;means for energizing said driving'means; and a relay system adapted tomaintain said driving means operative while a sound modulation groupcarried by said film is moving past said relay pick-up and during anyspace period between said sound modulation group and a succeeding soundmodulation group, said relay system being adapted to stop said drivingmeans when a succeeding sound modulation group is moved past said relaypick-up, said reproducing and relay pick-ups being spaced a distancecorrelated to the lag of said relay system and driving means wherebysaid reproducing pick-up is in position to reproduce the succeedingsound modulation group in its entirety upon a succeeding energization ofsaid driving means.

3. In a machine for the manipulation of strip film carrying a pluralityof sound modulation groups in succeeding spaced relation, thecombination of: a drum adapted to carry strip film, a motor drive forsaid drum, an electromagnetic clutch and brake element operativelyconnecting said drum and motor; a reproducing pick-up in operativerelation to said film on said drum; a relay pick-up in advance of saidreproducing pickup, and a relay system operatively connected to saidrelay pick-up, said relay system including a relay adapted to energizesaid clutch and brake elements in the alternative, and a holding circuitadapted to hold said brake element inoperative until a secondary soundmodulation group is in operative position with respect to saidcontrolling relay pick-up.

4. In a machine for the manipulation of strip film carrying a pluralityof sound modulation groups in succeeding spaced relation, thecombination of: a drum adapted to carry strip film, vacuum means forretaining film on said drum, a motor drive for: said drum, anelectromagnetic clutch and brake element operatively connecting saiddrum and motor; a reproducing pick-up in operative relation to said filmon said drum; a relay pick-up in advance of said reproducing pick-up,and a relay system operatively connected to said relay pick-up, saidrelay system including a relay adapted to energize said clutch and brakeelements in the alternative, and a holding circuit adapted to hold saidbrake element inoperative until a secondary sound modulation group is inoperative position with respect to said controlling relay pick-up.

5. In a machine for the manipulation of strip film carrying a pluralityof sound modulation groups in succeeding spaced relation, thecombination of: a drum adapted to carry strip film, vacuum means forretaining film on said drum, a motor drive for said drum, anelectromagnetic clutch and brake element operatively connecting saiddrum and motor; a reproducing pick-up in operative relation to said filmon said drum; a relay pick-up in advance of said reproducing pick-up,and a relay system operably connected to said relay pick-up adapted tomaintain said clutch element operative while a sound modulation groupcarried by said film is moving past said relay pick-up and during anyspace period between said sound modulation group and a succeedingmodulation group, said relay system including a relay energized directlyby said controlling relay pick-up, and means for selectively energizingsaid brake element upon a secondary energization of said directlyenergized relay by said control relay pick-up.

6. In a machine for manipulating strip film carrying a plurality ofsound modulation groups in succeeding spaced relation, the combinationof: a drum adapted to carry strip film, a motor drive for said drum, anelectromagnetic clutch and brake element operatively connecting saiddrum and motor; a sprocket adapted to feed film to and take film fromsaid drum, a motor drive for said sprocket and means operated by filmbetween said sprocket and drum tending to equalize the speed of thesprocket to the speed of the drum. 7. In a machine for manipulatingstrip film carrying a plurality of sound modulation groups in succeedingspaced relation, the combination of: a drum adapted to carry strip film,a motor drive for said drum, an electromagnetic clutch and brake elementoperatively connecting said drum and motor; a sprocket adapted to feedfilm to and I take film from said drum, a motor drive for said sprocketand means operated by film between said sprocket and drum tending toequalize the speed of the sprocket to the speed of the drum, a pair ofpick-up devices in operative relation to film on said drum, one of saidpick-up devices being operably connected with said electromagneticclutch and brake means for controlling the rotation of said drum.

' 8. In a machine for manipulation of strip film carrying a plurality ofsound modulation groups in succeeding spaced relation, the combinationof: a drum adapted to carry strip film, a reproducing pick-up inoperative relation to film carried by said drum, and a control pick-upin operative relation to said film in advance of said reproducingpick-up.

9. In a machine for manipulation of strip film carrying a plurality ofsound modulation groups in succeeding spaced relation, the combinationof:

a drum adapted to carry strip film, a reproducing pick-up in operativerelation to film carried by said drum, and a control pick-up inoperative relation to said film in advance of said reproducing pick-up,and means operated by said control pick-up for controlling the rotationof said drum.

10. In a machine for manipulation of strip film carrying a plurality ofsound modulation groups in succeeding spaced relation, the combinationof a drum adapted to carry strip film, a reproducing pick-up inoperative relation to film carried by said drum, and a control pick-upin operative relation to said film in advance of said reproducingpick-up, and means for adjustably positioning said control pick-up withrespect to said reproducing pickup.

11. A method of manipulating strip film carrying a plurality of soundmodulation groups in spaced succession thereon, comprising intermittently moving the film past a reproducing unit, and automaticallystopping the film at points immediately in advance of a succeeding soundmodulation group carried by said film.

12. In a method of manipulating strip film carrying a plurality ofsoundmodulation groups in spaced succession thereon, the steps of inter?mittently moving the film, each period of movem-ent corresponding to thelength of film between the beginning of successive sound modulationgroups on said film.

13. In a method of manipulating strip film carrying a plurality of soundmodulation groups in spaced succession, the steps of intermittentlymoving the film past a pair of linearly spaced reproducing units,aurally reproducing the sound modulations by the latter of saidreproducing units, and controlling the intermittent movement of the filmby the first of said units.

14. A method of manipulating strip film carrying a plurality of soundmodulation groups in spaced succession thereon, comprisingintermittently moving the film past a reproducing unit,

the periods of movement corresponding to the length of film betweenbeginning points of successive modulation groups, automatically stoppingthe film at points immediately in advance of a successive modulationgroup carried by said film, and governing the stoppage of the film bymeans of said modulation groups.

15. In a machine of the character described, the combination of: a drumadapted to carry 10 strip film, a motor drive for said drum, anelectromagnetic clutch and brake element operatively connecting saiddrum and motor; a sprocket adapted to feed film and take film from saiddrum, a motor drive for said sprocket and means operated by film betweensaid sprocket and drum tending to equalize the speed of the sprocket tothe speed of the drum, said last named film-operated means comprising apair of arms connected to each other and pivotally mounted near saidpoint of connection, and rollers carried by said arms and in'engagementwith film between said sprocket and drum.

16. In a machine of the character described, the combination of: a drumadapted to carry strip film, a motor drive for said drum, anelectromagnetic clutch and brake element operatively connecting saiddrum and motor; a sprocket adapted to feed film and take film from saiddrum, variable speed motor means for driving the sprocket, and variableresistance means for changing the speed of said variable speed motor,said variable resistance means being operated by changes in film tensionon feed and take-up sides of said drum. 17. In a machine of thecharacter described,

the combination of: a drum adapted tocarry' strip film, a motor drivefor said drum, an electromagnetic clutch and brake element operativelyconnecting said drum and motor; a sprocket adapted to feed film and takefilm from said drum, variable speed motor means for driving thesprocket, variable resistance means for changing the speed of saidvariable speed motor, said variable resistance means being operated by apair of arms connected to each other and pivotally mounted near saidpoint of connection, and rollers carried by said arms and in engagementwith film between said sprocket and drum.

18. In a machine of the character described, the combination of: a drumadapted to carry strip film, a motor drive for saiddrum, anelectromagnetic clutch and brake element operatively connecting saiddrum and motor; a sprocket adapted to feed film to and take film fromsaid 55 drum, a motor drive for said sprocket and means operated by filmbetween said sprocket and drum tending to equalize the speed of thesprocket to the speed of the drum; a reproducing pick-up in operativerelation to said film on said drum; a

relay pick-up in advance of said reproducing' pick-up, and a relaysystem operatively connected to said relay pick-up, said relay systemincluding a relay adapted to energize said clutch and brake elements inthe alternative, and a holding circuit adapted to hold said brakeelement inoperative until a secondary sound modulation group is inoperative position with respect to said controlling relay pick-up.

19. In a machine of the character described, the combination of: a drumadapted to carry strip film, vacuum means for retaining film on saiddrum, a motordrive for said drum, an electromagnetic clutch and brakeelement operatively connecting said drum and motor; a reproducingpick-up in operative relation to said film on said drum; a relay pick-upin advance of said reproducing pick-up, means for adjustably positioningone of said pick-ups with respect to the other, and a relay systemoperatively connected to said relay pick-up, said relay system includinga relay adapted to energize said clutch and brake elements in thealternative, and a holding circuit adapted to hold said brake elementinoperative until a secondary sound modulation group is in operativeposition with'respect to said controlling relay pick-up.

20. In a device of the character described, the combination of a hollowrotatable drum adapted to carry strip film, means for rotating saiddrum; apick-up device in operative relation to film on said drum, saiddevice including a light source, lens system and a responsive cellexteriorly of the drum and a reflective member positioned within theperiphery of said drum; a second pick-up device in operative relation tosaid drum and including an adjustable base carrying a light source, lenssystem and light responsive cell and an adjustably positionablereflective member within the periphery of said drum; said pick-updevices being in spaced linear relation with respect to film on thedrum, and means operated by one of said pick-up devices for controllingthe rotation of said drum.

21. In a device of the character described, the combination of: a hollowrotatable drum adapted. to carry strip film, means for rotating saiddrum, an end closure forsaid drum, means for supplying vacuum to saiddrum; ports in the face of said drum whereby vacuum may be applied tofilm carried thereon; a pick-up device in operative relation to film onsaid drum, said device including a light source, lens system andaresponsive cell exteriorly of the drum and a reflective memberpositioned within the periphery of said drum; a second pick-up device inoperative relation to said drum and including an adjustable basecarrying a light source, lens system and light responsive cell and anadjustably positionable reflective 'member Within the periphery of saiddrum; said pick-up devices being in spaced linear relation with respectto film on the drum; and means operated by one of said pick-ups forcontrolling the rotation of said drum.

GEORGE P. REGAN. CHARLES S. FRANKLIN.

